Telescoping lift-type gasholder



March 16, 1954 w. PERKINS 2,672,409

TELESCOP ING L IFT TYPE GASHOLDER Original Filed Sept. 10, 1945 3Sheets-Sheet l WHL 1-52 F PER/(INS March 16, 1954 w PERK|NS 2,672,409TELESCOPING LIFT-TYPE GASHOLDER Original Filed Sept. 10, 1945 5Sheets-Sheet 2 g woe/wim- W/IL 1-512 F. PERKINS March 16, 1954 w. F.PERKINS TELESCOPING LIFT-TYPE GASHOLDER OriginalFiled Sept. 10, 1945 5Sheets-Sheet S gnaw/Mm W44 7-52 F. PER/(1N3.

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Patented Mar. 16, 1954 UNITED STATES PATENT OFFICE TELESOOPING LIFT-TYPEGASHOLDER Walter F. Perkins, Baltimore, Md., assignor to KoppersCompany, Inc., Pittsburgh, Pa., a corporation of Delaware Originalapplication September 10, 1945, Serial No. 615,337. Divided and thisapplication May 2, 1947, Serial No. 745,588

A further object of th invention is to provide an improved gas holder ofthe type described and in which the mounting surfaces and guide rollerunits are arranged to permit the guide roller units to be adjustedradially and laterally of the holder sections.

Another object of the inventionis to provide an improved guide rollerunit which is adapted to be incorporated in a gas holder of the typetion Ser. No. 615,337, filed Sept. 10, 1945, now described,

Patent 2,551,373, issued u e 0, 1950. A further object of the presentinvention is to Telescoping ype gas holders u y have provide an'improvedguide roller unit of the type cylindrical sections which slidevertically within d ibed which is extremely rugged and is capaeachother, while these sections are surrounded m of withstanding substantialforce.

y a ui frame s ru r w i h includes v Another object of the invention isto provide tical guide members located at spaced points about theholder. The movable sections of a holder are provided with rollers whichare adapted to roll on surfaces on the vertical guide members to guidethe holder sections during their movement between their expandedpositions and their collapsed positions.

Gas holders usually are relatively large structures and haveconsiderable surface area with the result that relatively large forcesare exerted on the gas holder sections at times, as for example duringhigh winds. The guide rollers must guide the holder sections and permitthem to move freely at all times. Hence, the guide rollers andsupporting means therefore must be rugged enough to withstand relativelygreat forces.

Although gas holder sections and the associated guide frame structureare fabricated and erected with a high degree of skill, it ispractically impossible to initially position the rollers so that theywill accurately guide the gas holder sections without binding on theguide members and interfering with free movement of the holder sections.It is usually necessary after erection of a holder and the associatedguide frame structure to adjust the guide rollers during initialmovement of the holder sections between their collapsed and expandedpositions to insure that each section is free to move in all portions ofits range of movement and to also insure that each section is accuratelyguided in all portions of its range of movement.

rollers adapted to roll on surfaces on the guide members.

a guide roller unit of the type described which can be readily andeconomically constructed from standard structural members.

A further object of the invention is to provide an improved guide rollerunit of the type described which can be fabricated as a complete unitand shipped to the point of installation.

Another object of the invention is to provide an improved guide rollerunit of the type described which can be readily installed and whichincorporates means to readily permit the adjustments which are requiredto insure proper operation of the roller units and of the holdersections.

A further object of the invention is to provide an improved guide rollerunit of the type described in which the rollers are supported on astructure fabricated from a plurality of elements which are arranged sothat the various elements reinforce and strengthen each other so thatthe rollers are rigidly supported and will be maintained in accuratealignment when subjected to forces of great magnitude.

Other objects of the invention and features of novelty will be apparentfrom the following description taken in connection with the accompanyingdrawings in which Figure 1 is a fragmentary sectional view of anexpanded multiple lift gas holder provided by this invention;

Figure 2 is a fragmentary sectional view of the gas holder shown inFigure 1 with the sections of the holder shown in their collapsedpositions;

Figure 3 is a plan View of one of the guide roller units employed in thegas holder shown in Figures 1 and 2 and Figure 4 is a side elevation ofthe guide roller unit shown in Figure 3.

Lift-type gas holders are commonly used for grip; 42: lies inside the:cup: 40.

3 the storage of gas in quantities in the order of from 50,000 to15,000,000 cubic feet. Such gas holders are constructed with one or morelifts whereby the volume of the gas holder may be in creased ordecreased as required to accommodate the supply.- of gas onhand.Suchlift-type gas holders. as are more particularly illustrated inFigures 1 and 2, are constructed with a circular tank l adapted to holdwater at least in the por;--

tion adjacent the periphery, aguide-frame structure indicated generallyby the reference numeral l2, and a gas-tight bell indicated. generallyby the.

Although only one; vertical guide member it is illustrated in thedrawings, it is to be understood that the guideframe. structure l2includesav plurality of such. guide. members, and that they are locatedat uniform intervals about the circumference of the gas holder, as iscustomary in gas holders of this type. Likewise, itiscontemplated thatadjacentvertical: guide members is may be connected. together withbracesand tie rods, not shown, to maintain them in, their vertical positions.and to assist them; in withstanding the forces to whichtheyaresubjected.

The present invention relates particularly to gas holders of the generalcharacter described above and incorporates in such a structure certainfeatures of novelty as will be pointed out whichprovide a strongerstructure; which may be assembled in less-time andyor. withiless laborthan structures heretofore available in the prior art.

In a multiple-lift gasholder' the skirt. and skirt extensions areseverally known-as lifts. The skirt and extensions 2-21 and 24.consequently may be referred'to'hereinsometimes. as lifts20, 22 and 24,respectively;

Each pair of adjacent lifts is provided with complementary gripping andsealing means as best shown in: Figure 2, whereby the inner lift of thepair, as it is raised; engages and. lifts the outer one: of the pairwith a gas-tight engagement. Suitable gripping,- and sealing means as.illustrated. comprise hydraulic cups: 40 and. grips 42 formed in. theshaperof' anupwardlyopening annular channel, and adownwardly openingannular channel, respectively, of such. dimensions that the inner radiusofthe grip is intermediate the outer and. inner? radii. of 131182811X).Hence-, in the expanded? position, the outer: side 44 of cup 40 liesinside the grip 42 and the insidewall 4B of the The wall 46 of the grip42. is:- thus; immersed inthe water retained in the cup 40 and forms agas-tight. wallin the: expandedpositioni. depth ofthe; cup it is.desirably" eq at to: the: depth. of. the. grip: 42. so

thatthetop. edge of. wall. 44 of. the cup, 4% willengage the top 48 ofthe grip 42 at the same. time that the bottom edge of the-wall 4.5 ofthe grip 42 engages the-bottom 50 of the cup 40. Inner Wall 52 of cup 40also forms part of thelift. Desirablyi though. not. necessarily,. the.wall; 52. is, made of separate sheets weldedto. theremainder of: the

. lift... The. outer wall. 5.4 of the. grip. 4a is. similarly til 4constructed. The sheets forming the walls 44, 46, 48, 50, 52 and 54desirably are made of heavier stock than the other portion of each liftin order to give added strength to the lift structure. At the bottom ofthe outermost lift 24 there is providedan outpturned annular flange 56inplace of a cup. It is constructed-as the cup 40 except the outside wall44 is omitted. Similarly no grip is provided at the top of the innermostlift 20. There is provided instead a circular convex dome or roof 58welded at its periphery to the top of the lift, thereby formingwith thelifts 20, 22 and 24 thegas-tightbell I4. If desired, the height of thelift, 20: may be; extended by means of plates 50 welded to the top ofthe skirt and in turn to the periphery; ofxthe' dome. The height of theinner lift 20* is :thus madeequal to that of the other lifts.

In the Ianded'orcollapsed position the dome, as showndn Figure 2, issupported against collapse by a supporting structure 6! of any suitabledesign. Inasmuchassuch. structures are common in the: art. it will notbe. necessary to describe them. in. detail.

As'explainedin my application identified above, the. lifts are. providedwith vertical strengthening guide. rails which extend along the insideof the lifts over therentireheightof the. lifts. The guide rails areattached at-intervals. around the entire periphery of the inside ofeach. lift. Rollers are secured to the bottomsof the rails which have amounting to place. the. rollers on the outside of the lifts in positionto engage therails secured to thev next lift. outside of the lift. onwhich the rollers aremounted. These. guide rails and rollers keep; the;lifts in proper spaced relation to the tank and the nextadjacent lift asthe lifts are raised and lowered toprovide for changes in volume of gasin the holder. Reference is made to application, Ser. No. 615,337 for,the details of construction. ofthe guide rails. and rollers since thesedetails of. construction are not essential to an understanding of theparticular invention described and claimed. herein.

The present invention. relates particularly to the. roller guide units,which are mounted around the-outside periphery at the tops of each ofthe lifts.v These roller guide-units cooperate with rail guides; l8?mounted inand forming a part of the guide frame structure it whichsurrounds the holder. Toposition. the guide units on the lifts an angle:is provided atthe. topcf the outside of the lifts 22' and. 24 at theintersection of the top 48- and inner'sideiifi of thegrips The side 46is projected a suitable distance above the top plate 48 for thispurpose. Supporting structures till and; 08 for the outside rollers Hi3and 20 are: suitably fastened in. these angles as more clearlyshowninFigure. 2. A supporting structure H0 is mounted on the. dome 53. Theoutermost plates; H2 of the dome desirably are made ofheavystools. andare reinforced by brackets i it toprovide anadequately strong base forsupport H0.

It is to be understood. that a plurality of supporting structures: m1...m8 and i I 9. areprovitled, there;beinggone-cfieach of thesesupportingstructures radially inwardly of each of the vertical guide members. 13..As. is best: shown in Fig. 2 of the drawings, the supporting structuresextendradially outwardly so that each terminates adjacent-theinner faceof one of the guide memhers H3- Inaddition, as isclearlv shovinin Fig. 2of. the drawings, the. supporting-, structures. I01, we and. U0 are,proportionedso. that whenthe lifts of the holder are in their collapsed.position the supporting structure I08 projects over the supportingstructure I01, while the supporting structure I I projects over thesupporting structure I08.

Each of the supporting structures has adjacent its radially outer end asubstantially horizontal mounting surface which is adapted to havedetachably secured thereon a guide roller unit indicated generally bythe reference numeral I I6 and carrying rollers I I8 and I which areadapted to roll on guide surfaces on a vertical guide member I8. One ofthe supporting structures I0,! is illustrated in Figs. 3 and 4 of thedrawings and as therein shown the mounting surface is formed by a flatplate I50. It is to be understood that each of the supporting structuresI88 and H0 is provided with a similar substantially horizontal mountingsurface adjacent its outer end and on which is secured a guide rollerunit II6 of th type shown in Figs. 3 and 4.

Mounted on the mounting surface of each of the supporting structuresI01, I08, and H0, is a guide roller unit II6. Each of these guide rollerunits has three rollers, designated I I8 and I20, journaled in suitablesupports. mounted on parallel axes and are positioned to roll upon theflanges I22 of- I-shaped vertical guide member I8 mounted in a verticalposition on the guide-frame structure I2, whereas the roller I20 ismounted with its axis normal to the axes of the rollers II 8 and ispositioned to roll upon the web I26 of guide member I8. The guidemembers I8 are suitably supported on the guide-frame structure I2 by asuitable supporting means I28 in positions which preferably are radiallyoutwardly of the guide surfaces on the interior of the lifts 24 and 22so that the outside roller I20 areradially in alignment with at leastsome of the inside rollers. The supporting struc- I8 is suitablyfastened to the leg I30 of the support I28, as by welding. Thesupporting means I28 on which the vertical guide members I8 are securedmay be vertical extensions of the members I64 which are secured to theexterior face of the plates forming the wall of the tank I0, as isclearly illustrated in Fig. 2.

Each of the guide roller units H6 comprises a channel-shaped bracket I32having a web I34 and side flanges I36. on the channel I32 by the shaftsor trunnions I38 which are provided with retaining heads I40 and projectthrough aligned holes in the side flanges I36. Suitable washers I42 andpins I44 complete the mounting of rollers II8. As already pointed out,the axes of the rollers I I8 and the axes of the shafts or trunnions I38are parallel. They are also normal to theside flanges I36 of the channelI32. The center roller I20 is mounted between two parallel plates I46which are welded, or otherwise fastened, to the web I34 and side flangesI36 ofthe channel I32. The plates I46 are parallel one to another andnormal to the side flanges I36 and the web I34. The plates I46 projectslightly beyond the front flange I36 of the channel I32 as requiredproperly to position the roller I20. The front flange I36 of the channelI32 is cut away as required to permit plates I46 s o;-to

.project andto permit'free rotation of the roller v I 20. The roller I20 revolves on a shaft; I48 which.

is normal to the shafts I38 and extends through Rollers H8 are Therollers H8 are mounted aligned holes in the plates I46. The web I34 ofchannel I32 is adjustably mounted on the mounting surface formed by aplate I50 which is secured in a horizontal position on top of each ofthe supports I01, I08, and H0. The web I34 is perforated withlongitudinally elongated slots I52, whereas the plate I 50 is providedwith correspondingly positioned transversely elongated slots I54, as isbest shown in Fig. 3 of the drawmgs.

The slots I52 in the web I34 of the channel I32 and the slots I54 in theplate I50 are located in such manner that when the channel I32 is placedon the plate I50 the centers of the slots in the channel substantiallycoincide with the centers of the slots in the plate. The channel I32 isfastened to the plate I50 by suitable fastening means, such as the boltsI56. By loosening the bolts I56, the channel I32 may be shiftedtransversely throughout the length of slots I56 and longitudinallythroughout the length of slots I52. Within limits, therefore, theposition of the guide roller units is easily adjustable both radiallyand laterally of the mounting surface.

The construction just described provides a guide roller unit I I6 whichcan be constructed economically and is very satisfactory. The channelI32, which is one of the principal parts of the guide roller unit, is astandard structural steel shape. This channel has great strength toresist forces in the plane of the Web I34 or of the flanges I36, but haslittle strength to resist twisting forces. However, the channel isreinforced and strengthened by the plates I46 which extend transverselyof the channel I32 and are secured to the web and flanges of thechannel. The plates I46 stiffen the channe1 and prevent twisting of thechannel with the result that the channel E32 provides a rigid supportfor the rollers II8. Similarly, the plates I46 are reinforced andstiffened by the channel I32, particularly by the flanges I36 which aresecured to the plates I46. Hence, the plates I46 provide a rigid supportfor the roller I20.

The shafts I38, on which the rollers I I8 are mounted, extend throughaligned holes in the flanges I36 on the channel I32. The flanges I36 arespaced apart a considerable distance so that the shafts I38 are rigidlyheld with respect to the channel I32 and the rollers II8 will not getout of alignment because of movement of the shafts I38 relative to thechannel I32. As explained above, the channel I32 is reinforced andstrengthened by the plates I46 so that the channel has great strength toresist twisting forces, that is, forces tending to move the shafts I38out of alignment with each other. Furthermore, the bolts I56 whichsecure the channel I32 to the plate 50 are located directly beneath theshafts I38 so the plate I50 is effective to reinforce the channel and toprevent twisting of the channel which would result in misalignment ofthe shafts I38. The guide roller unit II6, therefore, rigidly maintainsthe rollers I I8 and I20 in alignment even under conditions inwhichsubstantial forces are exerted on the rollers, asfor example during ahigh wind storm. As the rollers II8 and I 20 are maintained in alignmentat all times, the rollers roll freely on the guide members I8 and do notinterfere with movement of the lifts of the holder.

The invention may be more fully -understood by referring generally tothe method-of construc- 7. welding together sheets uponasuitablefoundation. The bottom is circular, while I-beams I68 may bewelded. along radii at intervals alongthe bottom I58 to hold the lifts2B, 22, and 24 off the bottom. About the circumference of this bottom isthen erected the wall. of the tank. The wall of the tank is suitablyformed by welding together steel plates. As more clearly shown in Figure2, these plates may be proportioned in weight according to the pressureof water that they are required to support. Thus the bottom plate 160may be substantially thicker than the top plate I52.

The guide-frame structure I2 is built up from the top of the tank I!) inthe customary manner. Suitable reinforcing beams I54 project downwardlyfrom this guide-frame structure and are welded to the exterior wall ofthe tank Ii].

Either before or after or simultaneously with the building up of thetank and the guide-frame structure I2, the lifts are fabricated in theposition shown in Figure 2, and prior to this, or afterward, orsimultaneously therewith, the supporting structure BI is erected inaccordance with the usual practice in the art.

The outside roller supports I01, I08, and H are welded in place eitherafter or during construction. of the lifts. The guide roller units I16are then mounted and are initially adjusted.

The tank Ill is now filled with water and air is pumped into the tank asrequired to raise the bell I4. As the bell I4 is being raised, the guideroller units H6 are adjusted as required to permit unrestrained movementof the lifts of the holder and at the same time insure that the liftswill be accurately guided by the guide rollers.

In addition during this initial raising of the lifts of the holder, workmay be performed on them, as for example completion of the welding ofthe seams in these sections.

The adjustable guide roller units provided by this invention make itpossible effectively and economically to effect the above-describedoperations of adjusting the guide roller units and of welding the seamsin the lifts. By the simple expediency of loosening bolts, it ispossible to realign or adjust the guide roller units both radially andlaterally as maybe necessary to accommodate the particular requirementsof the gas holder. a lift-type gas holder that adjustment of the guideroller units need not be made during the initial operations. Practicesheretofore available make it diificult to do this and have materiallyincreased the cost of construction since the number of manhours lostduring such adjustments has been relatively large.

From the foregoing it will be seen that I have provided an improved gasholder incorporating adjustable guide roller units. The lifts of theholder have secured thereon the supporting structures I 01, I98, and H0which have horizontal mounting surfaces adjacent the inner faces of thevertical guide members I8. These mounting surfaces are adapted to havesecured thereon the guide roller units H6 which carry the rollers H8 andI20 which roll on the faces of the vertical guide members I8. Asexplained above, the guide roller units H6 hold the rollers H8 and IE0rigidly in alignment so that the rollers move freely on the surfaces ofthe vertical guide members l8 even when subjected to forces ofsubstantial magnitude. In addition, it will be seen that'the guiderollerunlt U 6 re pted to be construoted as complete units and It isnotpractically possible so to construct shipped tothe point ofinstallation. Furthermore, these units are quickly and easily installedby placing the units on the mounting surfaces on the supportingstructures I01, I08, and H6, and installing the bolts I56. After a guideroller unit has been installed it can be readily adjusted both radiallyand laterally of the associated mounting surface so that the rollerscarried by the unit will engage the faces of the guide members I8 butwill not bind on these members or press against them so much as tointerfere with movement of the lifts of the holder. As the adjustment ofthe guide roller units can be quickly and easily accomplished, thisadjustment will not delay other work which may be in progress duringinitial raising of the lifts of a holder.

While I have described my invention with reference to particularembodiments thereof, it will be under-stood that variation may be madetherein without departing from the spirit and scope of the invention.

I claim:

1. In a gas holder comprising a tank, a guideframe structure mountedthereon and a gastight bell adapted for vertical movement within saidtank and guide-frame structure, the combination of guides mounted on theinterior of said guide-frame structure, each of said guides having aplurality of vertical rolling surfaces, a plurality of roller unitsmounted on supporting means affixed to said bell each of said unitshaving a plurality of rollers adapted to roll upon the rolling surfacesof said guides, each of said units comprising a channel-shaped memberhaving a web resting on a flat supporting plate comprised in saidsupporting means and having flanges at each side thereof normal to theradius projecting through said guides, a pair of rollers mounted onparallel trunnions projecting through the flanges of said channel, andanother roller mounted on an axle supported between and normal to saidparallel trunnions in two parallel plates mounted transversely of saidchannelshaped member and fastened to the flanges and web thereof.

2. In a gas holder of the type having a guide frame comprising aplurality of substantially vertical guide members arranged at spacedpoints about the circumference of a circle, each of said guide membershaving on the side thereof facing the center of said circle atangentially disposed vertical guide surface and having a 'pair ofradially disposed vertical guide surfaces and a gas-tight bell adaptedfor vertical movement within said guide frame, said bell having on itsexterior face radially inwardly of each of said vertical guide members asubstantially horizontal mounting surface having therein a plurality ofholes all of which are elongated in the direction of the plane of one ofthe vertical guide surfaces on the adjacent vertical guide member, thecombination with the foregoing of an improved guide roller unit, saidunit comprising a channel shaped member having a web resting on saidhorizontal mounting surface and having flanges at each side of the webrunning parallel to said tangentially disposed guide surface, a pair ofspaced parallel plates disposed substantially perpendicular to the faceof said channel member and extending transversely of said channelmember, each of said plates being secured to the web and to the flangesof said channel member and being located adjacent the midpor ion of saidchannel, an axleextending through al gned openings'ill said plates andhaving supported thereon between said plates a tangentially disposedroller adapted to roll on the first vertical surface on one of saidvertical guide members, the flanges on said channel member havingaligned openings therein to one side of said plates and aligned openingsto the other side of said plates, each pair of aligned openings havingsupported therein a trunnion extending from a side face of the channelmember and having mounted thereon a roller which is adapted to roll onthe radially disposed guide surface on one of said vertical guidemembers, the web of said channel member having therein a plurality ofholes which are elongated in the direction perpendicular to that inwhich the holes in the supporting surface are elongated, the holes inthe web of the channel being located so that when said channel member isplaced against said mounting surface the centers of the holes in thechannel and in the supporting surface substantially coincide, and boltsextending through the holes in the web of said chamiel member and insaid supporting surface.

3. In an improved guide roller unit for multiple-lift-type gas holdersin combination: a tank, a closed lift mounted within the tank, aguideframe surrounding the lift and mounted on the tank, vertical guidesmounted in the frame in spaced relationship around the lift, asupporting structure secured to the upper peripheral surface of a liftand having a flat supporting surface, a channel-shaped member having aweb resting on said flat supporting surface and having flanges at eachside of the web running normal to a radius of the lift running above thecenter of said web, a pair of spaced parallel plates disposedsubstantially perpendicular to a tangential- 1y disposed face of saidchannel member and extending transversely thereof, each of said plates10 being secured to the web and to the flanges of said channel member,said plates being located adjacent the mid portion of the channelmember, an axle extending through aligned openings in said plates andhaving supported thereon between said plates a first roller adapted toroll on the guiding surface of a vertical guide, the flanges on saidchannel having aligned openings therein to one side of said plates andaligned openings therein to the other side of said plates, each pair ofaligned openings having supported therein a trunnion extending from aside face of said channel and having mounted thereon a second rollerrotatable about an axis perpendicular to the axis of said first roller,each of said second rollers being adapted to roll on radially disposedguiding surfaces of the vertical guide, the web of said channel havingtherein a plurality of holes which are adapted to receive bolts by meansof which said assembly may be secured in adjusted guiding position onthe surface of the supporting structure.

WALTER F. PERKINS.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 8,648 Joy Oct. 9, 1866 428,125 Newell May 20, 1890 972,785Stofiels Oct. 11, 1910 1,494,818 Shean May 20, 1924 1,765,946 Shea June24, 1930 1,886,101 Jagschitz Nov. 1, 1932 2,367,497 Greuning Jan. 16,1945 FOREIGN PATENTS Number Country Date 572,628 France Feb. 3, 1924809,494 France Dec. 12, 1936

1. IN A GAS HOLDER COMPRISING A TANK, GUIDEFRAME STRUCTURE MOUNTEDTHEREON AND A GASTIGHT BELL ADPTED FOR VERTICAL MOVEMENT WITHIN SAIDTANK AND GUIDE-FRAME STRUCTURE, THE COMBINATIN OF GUIDES MOUNTED ON THEINTERIOR OF SAID GUIDE-FRAME STRUCTURE, EACH OF SAID GUIDES HAVING APLURALITY OF VERTICAL ROLLING SURFACES, A PLURALITY OF ROLLER UNITSMOUNTED ON SUPPORTING MEAN AFFIXED TO SAID BELL EACH OF SAID UNITSHAVING A PLURALITY OF ROLLERS ADAPTED TO ROLL UPON THE ROLLING SURFACESOF SAID GUIDES, EACH OF SAID UNITS COMPRISING A CHANNEL-SHAPED MEMBERHAVING A WEB RESTING ON A FLAT SUPPORTING PLATE COMPRISED IN SAIDSUPPORTING MEANS AND HAVING FLANGES AT EACH SIDE THEREOF NORMAL TO THERADIUS PROJECTING THROUGH SAID GUIDES, A PAIR OF ROLLERS MOUNTED ONPARALLEL TRUNNIONS PROJECTING THROUGH THE FLANGES OF SAID CHANNEL, ANDANOTHER ROLLER MOUNTED ON AN AXLE SUPPORTED BETWEEN AND NORMAL TO SAIDPARALLEL TRUNNIONS IN TWO PARALLEL PLATES MOUNTED TRANSVERSELY OF SAIDCHANNELSHAPED MEMBER AND FASTENED TO THE FLANGES AND WEB THEREOF.